"He's the one who really pushed us to begin selling our service. Scott [Heiferman] and I were both concerned; we weren't sure how member growth would be effected. We assumed a pay wall would stall growth, because it's an additional (significant) hurdle.

"But Pierre was confident in the paying model and he predicted exactly what would happen. He said customers would be livid at first. They'd threaten us, trash us, and nearly all of our them would disappear over night. After that, Pierre was confident our customers would start coming back.

"That's exactly what happened. The big lesson from Pierre was realizing that a paywall would create a growing group of evangelists for the company and cause member growth to actually accelerate. Now Meetup is more profitable than ever."